From: Jiri Slaby <jslaby@suse.cz>
To: linux-kernel@vger.kernel.org
Cc: jirislaby@gmail.com, Vojtech Pavlik <vojtech@suse.cz>,
Michael Matz <matz@suse.de>, Jiri Kosina <jkosina@suse.cz>,
Jiri Slaby <jslaby@suse.cz>, Steven Rostedt <rostedt@goodmis.org>,
Frederic Weisbecker <fweisbec@gmail.com>,
Ingo Molnar <mingo@redhat.com>
Subject: [RFC 01/16] ftrace: Add function to find fentry of function
Date: Wed, 30 Apr 2014 16:30:34 +0200 [thread overview]
Message-ID: <1398868249-26169-2-git-send-email-jslaby@suse.cz> (raw)
In-Reply-To: <1398868249-26169-1-git-send-email-jslaby@suse.cz>
This is needed for kgr to find fentry location to be "ftraced". We use
this to find a place where to jump to a new/old code location.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
---
include/linux/ftrace.h | 1 +
kernel/trace/ftrace.c | 29 +++++++++++++++++++++++++++++
2 files changed, 30 insertions(+)
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index ae9504b4b67d..8b447493b6a5 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -299,6 +299,7 @@ extern void
unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
extern void unregister_ftrace_function_probe_all(char *glob);
+extern unsigned long ftrace_function_to_fentry(unsigned long addr);
extern int ftrace_text_reserved(const void *start, const void *end);
extern int ftrace_nr_registered_ops(void);
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 4a54a25afa2f..9968695cdcf9 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1495,6 +1495,35 @@ ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs)
} \
}
+/**
+ * ftrace_function_to_fentry -- lookup fentry location for a function
+ * @addr: function address to find a fentry in
+ *
+ * Perform a lookup in a list of fentry callsites to find one that fits a
+ * specified function @addr. It returns the corresponding fentry callsite or
+ * zero on failure.
+ */
+unsigned long ftrace_function_to_fentry(unsigned long addr)
+{
+ const struct dyn_ftrace *rec;
+ const struct ftrace_page *pg;
+ unsigned long ret = 0;
+
+ mutex_lock(&ftrace_lock);
+ do_for_each_ftrace_rec(pg, rec) {
+ unsigned long off;
+ if (!kallsyms_lookup_size_offset(rec->ip, NULL, &off))
+ continue;
+ if (addr + off == rec->ip) {
+ ret = rec->ip;
+ goto end;
+ }
+ } while_for_each_ftrace_rec()
+end:
+ mutex_unlock(&ftrace_lock);
+
+ return ret;
+}
static int ftrace_cmp_recs(const void *a, const void *b)
{
--
1.9.2
next prev parent reply other threads:[~2014-04-30 14:34 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-04-30 14:30 [RFC 00/16] kGraft Jiri Slaby
2014-04-30 14:30 ` Jiri Slaby [this message]
2014-04-30 14:48 ` [RFC 01/16] ftrace: Add function to find fentry of function Steven Rostedt
2014-04-30 14:58 ` Jiri Slaby
2014-04-30 14:30 ` [RFC 02/16] ftrace: Make ftrace_is_dead available globally Jiri Slaby
2014-04-30 14:30 ` [RFC 03/16] kgr: initial code Jiri Slaby
2014-04-30 14:56 ` Steven Rostedt
2014-04-30 14:57 ` Jiri Slaby
2014-05-01 20:20 ` Andi Kleen
2014-05-01 20:37 ` Jiri Kosina
2014-05-14 9:28 ` Aravinda Prasad
2014-05-14 10:12 ` Jiri Slaby
2014-05-14 10:41 ` Aravinda Prasad
2014-05-14 10:44 ` Jiri Slaby
2014-05-14 11:19 ` Aravinda Prasad
2014-05-20 11:36 ` Jiri Slaby
2014-05-21 18:28 ` Aravinda Prasad
2014-05-26 8:50 ` Jiri Kosina
2014-04-30 14:30 ` [RFC 04/16] kgr: add testing kgraft patch Jiri Slaby
2014-05-06 11:03 ` Pavel Machek
2014-05-12 12:50 ` Jiri Slaby
2014-04-30 14:30 ` [RFC 05/16] kgr: update Kconfig documentation Jiri Slaby
2014-05-03 14:32 ` Randy Dunlap
2014-04-30 14:30 ` [RFC 06/16] kgr: add Documentation Jiri Slaby
2014-05-06 11:03 ` Pavel Machek
2014-05-09 9:31 ` kgr: dealing with optimalizations? (was Re: [RFC 06/16] kgr: add Documentat)ion Pavel Machek
2014-05-09 12:22 ` Michael Matz
2014-04-30 14:30 ` [RFC 07/16] kgr: trigger the first check earlier Jiri Slaby
2014-04-30 14:30 ` [RFC 08/16] kgr: sched.h, introduce kgr_task_safe helper Jiri Slaby
2014-04-30 14:30 ` [RFC 09/16] kgr: mark task_safe in some kthreads Jiri Slaby
2014-04-30 15:49 ` Greg Kroah-Hartman
2014-04-30 16:55 ` Paul E. McKenney
2014-04-30 18:33 ` Vojtech Pavlik
2014-04-30 19:07 ` Paul E. McKenney
2014-05-01 14:24 ` Tejun Heo
2014-05-01 20:17 ` Jiri Kosina
2014-05-01 21:02 ` Tejun Heo
2014-05-01 21:09 ` Tejun Heo
2014-05-14 14:59 ` Jiri Slaby
2014-05-14 15:15 ` Vojtech Pavlik
2014-05-14 15:30 ` Paul E. McKenney
2014-05-14 16:32 ` Tejun Heo
2014-05-15 3:53 ` Mike Galbraith
2014-05-15 4:06 ` Tejun Heo
2014-05-15 4:46 ` Mike Galbraith
2014-05-15 4:50 ` Tejun Heo
2014-05-15 5:04 ` Mike Galbraith
2014-05-15 5:09 ` Tejun Heo
2014-05-15 5:32 ` Mike Galbraith
2014-05-15 6:05 ` Tejun Heo
2014-05-15 6:32 ` Mike Galbraith
2014-04-30 14:30 ` [RFC 10/16] kgr: kthreads support Jiri Slaby
2014-04-30 14:30 ` [RFC 11/16] kgr: handle irqs Jiri Slaby
2014-04-30 14:30 ` [RFC 12/16] kgr: add tools Jiri Slaby
2014-05-06 11:03 ` Pavel Machek
2014-04-30 14:30 ` [RFC 13/16] kgr: add MAINTAINERS entry Jiri Slaby
2014-04-30 14:30 ` [RFC 14/16] kgr: x86: refuse to build without fentry support Jiri Slaby
2014-04-30 14:30 ` [RFC 15/16] kgr: add procfs interface for per-process 'kgr_in_progress' Jiri Slaby
2014-04-30 14:30 ` [RFC 16/16] kgr: make a per-process 'in progress' flag a single bit Jiri Slaby
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